While cryptocurrency mining specific GPUs will be hitting the market soon, the current stock of GTX 1070's, 1060's, Radeon RX 580's and so on have been bought up by the flood of demand from miners. All that remains are cards at inflated prices, so if you were going to build a new gaming rig this Summer it's probably best to put it off until prices return to sanity. That said, it's also the 4th of July sales season, and Lenovo, HP, and even GameStop have a few old desktop models with gaming GPUs on the cheap.
While you use to find GTX 1060 cards for $200, the current demand has prices in the $300 - $600 range. It's crazy how much the cards are going for these days, but thanks to the sales Lenovo's Y710 Cube desktop, HP's Omen 870, and CyberPowerPC's Game Master desktop all have configurations with GTX 1060's at pretty good prices. All under $1,000.
Our personal pick would be the older generation but clearance priced Lenovo Y710 Cube (which is now dubbed the Lenovo Legion Cube). Priced at only $650, you'll get a mid-range Radeon RX 480 along with a Quad Core i5-6400. This is a great price considering both used and new RX 480 are going for around $360 to $400 on eBay.
In budget selection, the cheapest is the HP Omen 870 desktop for $630. The Core i3-6100 and RX 460 isn't going to let you play modern titles at Ultra settings, but you should be able to play most recent titles at low-to-medium settings, which isn't too bad all things consider as the RX 460 is a lower mid-range GPU. Given the price discrepancy though, it's probably worth the money to spring for the extra $20 and get the Lenovo Cube.
Update: The higher spec Y710 Cube is now out of stock at Lenovo. Link for the HP Omen 870 with a GTX 1060 has now been updated as well as HP did a product URL update. Sorry about the confusion.
GTX 1060 Desktops Under $900
Lenovo Y710 Cube i7-6700, GTX 1060 6GB, 1TB + 128GB SSD, 16GB — $899 (list $1,350)- HP Omen 870 i5-6400, GTX 1060, 8GB, 1TB — $799.99 (list $900)
- CyberPowerPC Ryzen 5 1400, GTX 1060, 8GB, 1TB — $749.99 (list $750)
- CyberPowerPC Ryzen 7 1700X, GTX 1070, 16GB, 120GB SSD + 1TB — $1,349.99 (list $1,500)
- Lenovo Legion Y710 Cube i5-6400, Radeon RX 480, 1TB, 8GB — $689 (list $1,000)
- Lenovo IdeaCentre Y700 i5-6400, 8GB, 1TB, GTX 1050 Ti — $649 (list $820)
- HP Omen 870 i3-6100, Radeon RX 460, 8GB, 1TB — $629.99 (list $700)